Slideway lubrication



March 7, 1944. ,Q W, BURN'HAM Y 2,343,533

SLIDEWAY LUBRI CATION Filed Maron 16, 1942 f, #47M 44W 14M Patented Mar.7, 1944 SLIDEWAY LUBRICATION Clarence W. Burnham, Springfield, Vt.,assgnor to The Fellows Gear Shaper Company, Springfield, Vt., acorporation of Vermont Application March 16, 1942, Serial N0. 434,815

12 Claims.

The present invention relates to means and provisions for lubricatingthe Ways on which slides or carriages, or other moving parts of machinesare supported for reciprocating motion. Its object is to provide a moreadequate and copious lubrication of such slideways than is accomplishedby the means heretofore used and, in particular, to insure eective andadequate lubrication at the end of the slideway remote from that towhich the lubricant is supplied.

The common practice in connection with machines having elongatedslideways on which reciprocating slides are supported is to admit oil toone end of the slideway and to provide a series of grooves in thesurface of the slideway forming a continuous channel from the admissionpoint to the opposite end of the slideway. These grooves have heretoforebeen made of equal depth and width in all parts and frequently havefailed to accomplish adequate lubrication at, and for some distance backfrom, the outlet point. Lubrication in this manner has been more or lessuncertain and variable, depending on the clearance, the pressure, andthe width and depth of the grooves. It was not possible to determinejust how much of the slideway would be lubricated and how much oil wouldbe supplied to any given portion of its length. The present inventionavoids the defects and uncertainties of the prior practice and insuresan adequate and copious supply of oil to all parts of the slideway.

One embodiment of the invention and one of its possible modes ofapplication are shown in the accompanying drawing, in which- Fig. l is afragmentary side elevation of the supporting portion of a machine havingtwo parallel inclined guides or slideways, with a carriage or slidesupported for reciprocating motion thereon;

Fig. 2 is a cross section taken on line 2-2 of Fig. 1;

Fig. 3 is a plan view of one of the slideways with which the machine ofFig. l is equipped and in which the lubricating provisions of thisinvention are embodied;

Fig. 4 is a longitudinal section of the slideway taken on line 4-4 ofFig. 3;

Figs. 5, 6 and 7 are cross sections of the sldei way taken on lines 5 5,6 6 and 'I-'I respectively of Fig. 3.

Like reference characters designate the same parts Wherever they occurin all the figures;

The machine partially shown in Figs. 1 and 2 illustrates one of the manysituations in which the invention may be usefully applied. This machineincludes a slide o1' carriage I0, which rests and reciprocates on twoslideways or bars Il and I2 mounted on a supporting structure I3parallel to one another at an inclination to the horizontal. Thebrokenline structure in Fig. l represents a mechanism for moving theslide in the uphill direction, consisting of a cam I4 secured to a quillI5, which is mounted rotatably on the slide, and reacting against afixed abutment I6 on the supportingstructure. The quill is oscillated byan arm I and aconnecting rod I8` receiving motion from a crank notshown. Gravity moves the slide inthe opposite direction and maintainspressure contact between the cam and the abutment. However, thecharacter of the slide and the means for reciprocating it are immaterialto the present invention, which -is concerned wholly with the problemvof providing adequate lubrication between thesupporting surfaces of theslideways and the bearing surfaces of the slide.

Figs. 3 7 inclusive show theslideway II with all the details of form andstructure vby which effective supply and distributionv of lubricant isaccomplished in accordance with the present in-A vention. Both slidewaysVare alike-and the following description of one will suice for both.

In the upper surface of the slideway'are a l series of pockets orrecesses I9 and grooves 20- and 2I passing from each pocket to the next.

Oil is delivered to the pocket at one end of they series through achannel 22 extending inward.

from the adjacent end of the slideway and terminating in a port 23 whichis located in the upper surface of the slideway and intersects thenearer boundary 24 of the endmost pocket. A pipe for conducting the oilto the slideway may be screwed into the threaded entrance to the passage22 shown in the drawing. Where the slideway is mountedin n position, asin the present illustration,VV the'Oil is supplied to its upper end.VIEach pocket, isA of' progressively increasing depth ini 'the directionfrom the upper toward the lower endA o f the slideway, and is boundedat' thesidesand lower portion by a curvedwall251of progressive andcontinuous curvature. Preferably this curvature is circular and the wall125. iscylindricalyalthough these' latterl particularsare not 'of-theessence of the inventionandr may be Vvaried Within limitshereinafterjindicatedv.3 'lhejgroovesV 20 and 2| permit flow ofjoilfromeach pocket to the next, and are in "staggered relation to` onelanother. That' is, the grooves'Z; which lead an' inclined from the firstto the second pocket, from the third to the fourth, from the fifth tothe sixth, and so on, are located approximately on the tangents to thosepockets adjacent to one side of the slideway, while the grooves 2l,which lead from the second to the third pocket, from the fourth to thefth, from the sixth to the seventh, and so on, are located substantiallyon the tangents to 'those pockets adjacent to the opposite side of theslideway. And the port 23 opens into the first pocket near the sideopposite to that into which the pasage 2S opens. Thus the oil enterseach pocket at or near one side thereof and ows out of the pocket from apoint near the opposite side thereof. A groove 2-1 leads from the lastpocket of the lseries Vto a sump 28 from which a passage 29 leads tocon-` nection with an eduction pipe.

When the slide is supported on the guideways, it covers all the pocketsand connes the oil mainly to the pockets and intercommunicating grooves.Oil fed from the port 23 lls the rst pocket and flows thence to thesecond pocket through the groove 2Q, from the second to the third pocketthrough the groove 2|, and so on through the entire series entering eachpocket at one side thereof and issuing from the opposite side. Inpassing from the entrance to the outlet pointA of each pocket, the oilows along the curved wall and is given a swirling motion thereby, sothat it washes the overlying surface of the slide.v In the constructionhere illustrated the grooves 2U, 2| and 2! are much less deep than thedeepest parts of the pockets and their depth is so related to theinclination of the slideway, when set up for use, that the lowest pointsof their entrance ends are at higher levels than the lowest points ofthe bounding edges of the pockets from which they respectively lead.That is, owing to the tangential relation of each groove to the pocketfrom which it receives oil, its intersection with the pocket, in thesupporting plane of the slideway, is at a level higher than the upperedge of the curved Wall 25 and the depth ris lshallow enough to bringVVthe lowest point of its intersection with the pocket wall at a levelhigher than the level of the lowest point of the bounding edge of thepocket. This relation is illustrated by the broken line a in Fig. 4,which is the horizontal plane ofthe lowest point of the intersection 3'0between one ofthe pockets and the groove leading therefrom. This isVhigher than the lowest point, b, of the bounding wall of the pocket, andis the lowest point 4to which the oil level can fall when the pocket iscovered by the overlying slide. However, as oil is constantly beingsupplied to the pocket, the actual level is higher than the plane of theline a, and may be in the neighborhood of the plane indicated by thebroken line c. Hence each pocket will always contain a body of oil incontact with the overlying surface of the slide throughout aconsiderable proportion of the width of the pocket. This is equally thecase with the `pockets nearest the lower end of the slideway as withlthose near the upper end. The oil above the level a creates a pressurehead causing a copiousgush of oil from the pocket at higher level to theone next below. The pools of oil thus maintained and constantlyreplenished, at numerous points throughout the length of the slideway,furnish a copious and adequate lubrication to all parts of the slide; aswell near the end'from which the oil is dis-l charged aswat the end towhich oil is admitted.`

broken from the middle part of the slideway as shown, in order that itsend portions may be represented on a large enough scale within thelimitations of the drawing space.

Longitudinal grooves 3| and 32 are provided in the supporting surface ofthe slideway between [the side edges of the slideway and the pockets toreceive whatever oil may overflow or be forced out laterally between thesliding surfaces. These grooves open at their opposite ends into thesump 2S and a cross channel 33 in the upper end of the slideway.

The particular wedge shaped or ungular formation of the pockets l hereshown has been chosen partly as a measure of convenience, because suchpockets can be simply and economically made by the operation of an endmilling cutter fed into the surface of 'the slideway at an inclinationto that surface. This manner of cutting the pockets makes the boundingwall 25 perpendicular +o the bottom of the pocket. It also causes thewall 25 to be inclined at an obtuse angle to the supporting surface ofthe slideway throughout most of its extent. The angle is greatest at thelongitudinal median plane, as shown by Fig. 4, and it is considerablymore than through a substantial distance to each side of the medianplane. This slope of the wall 25 supplements the elect of centrifugalforce in causing the swirling current of oil to exert upward forceagainst the overlying surface of the sliding member l and to wash andscour that surface.

However, these details are not of the utmost importance and may bevaried or modified within the scope of the broader aspects of theinvention. A curved wall between the inlet and outlet points of thepocket is important because of the swirling and washing action given tothe oil thereby. But the curvature of such Wall may be other thancircular, and it may be disposed otherwise than as the curved surface ofan ungula. So great a depth in the deepest part of the pocket, as hereshown, is also not essential.

With the slideway arranged in an inclined position, adequate flow of oilmay be accomplished by gravity alone; although of course the force ofgravity may be supplemented by hydrostatic pressure. However, theutility of the invention is not limited to inclined slideways, but maybe applied to those which are horizontal as well, provided that the oilis supplied with sufficient pressure to cause it to flow through thepockets and grooves, to keep the pocketsl full of oil, and to obtain thedesired swirling motion of the oil in its passage through the successivepockets. Then to confine the oil, the slide must cover all the openpockets and grooves at all points in its reciprocating travel. This maybe accomplished either by making the slide longer than the slideways, orby providing extensions 34 and 35 on opposite ends of the slide ofsuicient length to cover the exposedend portionsv of the slidewayswhenthe slide is at either end'of fits stroke. f, i 12,1 w; WhataI claimand-,desire'to secure'fby :Letters Patent is: .i 1 .11" l. ,In a machinehaving-la sliding part; a guide or..slideway vhaving va supportingupper' surface on which an under surface of :said'slidingpart bears andby which the sliding partis supported, said= slideway' having pockets4rin, its= said .supporting surface arranged inlinear series, and havinga channel for fluid lubricant leading-to the Vfirst pocket ofthe seriesand other-channels mits supporting surface leading in'- series frompocket to pocket; said pockets being adapted to contain pools ofthelubricant in contact with theoverlying surface of the slidingmemberand tobe continuously replenishedbylubricant flowthrough saidchannels. v y :i 2. In a machine having a reciprocable sliding member,and an elongated guide or slideway extendingv in the direction..ofreciprocation of said sliding member having an upper supportingsurface on which an under surface of the sliding member rests,provisions for introducing lubricant between said surfaces of theslideway and sliding member consisting of pockets sunk into the uppersurface of the slideway extending across a substantial proportion of thewidth thereof and arranged in linear series extending in the directionof reciprocation of the sliding member, channels leading from eachpocket to the next in series, and a channel for delivering oil to thefirst pocket of the series; the channels between the pockets being ofless width than the pockets and located alternately at opposite sides ofthe pockets so that the port at which oil enters each pocket is at theopposite side from the port through which oil leaves the same pocket,whereby the pockets contain pools of oil in contact with the overlyingsurface of the sliding member and oil flowing progressively through theseries of pockets is given a cross current flow in passing between therespective inlet and outlet ports of the several pockets.

3. In a machine having an elongated guide or slideway arranged with itslength dimension at an inclination to the horizontal and its transversedimension horizontal, and a slide supported on said slideway forreciprocation up and down the slope thereof, provisions for lubricatingthe bearing surfaces of said slideway and slide comprising a series ofpockets sunk into the supporting surface of the slideway spaced apartalong the length dimension thereof and each occupying a Substantialproportion of the width dimension of said surface, a flow passageleading into the uppermost pocket of the series for delivering oilthereto, and transmission channels sunk into said supporting surface ofless width than the pockets leading from each upper pocket to the nextlower pocket of the series, the eduction connection between each pocketand a channel being of less depth than the depth of the pocket at itslower boundary.

4. In a machine having an elongated guide or slideway arranged with itslength dimension at an inclination to the horizontal and its transversedimension horizontal, and a slide supported on said slideway forreciprocation up and down the slope thereof, provisions for lubricatingthe bearing surfaces of said slideway and slide comprising a series ofpockets sunk into the-supporting .surface 'of the slideway spaced apartalong theflength dimension` thereof and Voccupying a=1 substantialproportion. 'of the-width dimension 'of/said surface, a flow passageleadinginto the uppermost "pocket of the: series ffor delivering oilthereto, and: transmission channels. .sunk into said supporting surfaceofzlesswidthlithan the pockets leading from .each upper pocket tothenextlower pocket of the series,- the eduction connection Vvbetweeneach pocketzand auchannel being mainly''at a'. level above the level ofthe lowest part ofthe lower boundaryof the pocket. 1 f i Y 5.1In amachine having a reciprocable sliding memberland Y af-guide. orIslideway supporting said member, provisions-for 'lubricating --thebearing asurfa'ces of-said sliding member and slidewaycomprisingwa".series o'f pockets sunk into the supportingsurface oftheslideway and spaced 1apart1in the direction of reciprocation v'of thesliding member, 'a channel for delivering oil to the pocket at :one endof the series and channels in the supporting surface leading from eachpocket to the next in series, said last named channels being of lesswidth than the pockets and being located with their respective points ofdelivery connection to the several pockets at the opposite side of therespective pockets from the points of eduction therefrom, and thebounding wall at the side of the pocket toward which the inletconnection is directed being curved with a concave curvatureprogressively to the eduction connection, whereby the oil in owingthrough the pockets from inlet to outlet is given a swirling motion incontact with the overlying surface of the sliding member.

6. In a machine having a sliding member and a guide or slideway on whichsaid member is supported and along which it may reciprocate, provisionsfor lubricating the bearing surfaces of said member and slidewaycomprising pockets sunk into the supporting surface of the slideway andspaced apart from one another along the line of movementof the slidingmember, conducting means for conveying oil to the pocket at one end ofthe series, a channel of less width than the pocket leading from aneduction port at one side of the rst pocket to an inlet port at thecorresponding side of the second pocket, a second channel similar to thefirst named channel leading from an eduction port at the opposite sidefrom the inlet port of the second pocket to an inlet port at thecorresponding side of the third pocket, and other channels betweensuccessive pockets of the series in alternating arrangement like thefirst and second channels precedently set forth, the several pocketseach having a bounding wall of concave curvature between the inlet andoutlet ports, which wall, in a portion of its extent, makes an obtuseangle with said supporting surface.

7. A guide or slideway for a machine having a sliding member, saidslideway being provided with an upper supporting surface having pocketsarranged to contain pools of oil and interconnecting channels forconducting oil to the endmost pocket and thence to the other pockets inseries.

8. A guide or slideway as set forth in claim 7, in which the channelsare of substantially less width than the pockets and respectively openinto and lead from the several pockets at opposite sides of the pockets,whereby a cross iiow of oil in the pocket is produced in flowing fromthe `inlet to the outlet port.

9. A guide or slideway as set forth in claim '7, in which one boundinglwall of each pocket is curved and the channels leading into and out ofthe pockets are substantially narrower than the pocket and located atrespectivelyy opposite sides thereof, with the inwardly rconductingchannel arranged to discharge oil tangentially of said curved wall,whereby the oil is given a swirling movement in flowing to the eductionport.

10. A guide or slideway having a plane supporting surface with a row ofpockets .spaced apart in said surface and channels leading from eachpocket to the next in series; each pocket having a concave curved wallat the side thereof toward the next pocket in series, and the channelleading into the pocket being of less width :than the pocket and locatedat one side thereof substantially tangential to said wall, while thechannel leading from the pocket opens through said Wall at the side ofthe pocket opposite to the leading in channel. A

11. A guide or slideway as set forth in claim 10, in which the curvedwall makes an obtuse angle with the said plane surface in at least aportion of its extent between the leading in and eduction channels.

12. A guide or slideway for the purposes set forth having a planesupporting surface with e row of pockets sunk in said surface andchannels leading from pocket to pocket in series; each pocket being ofprogressively increasing depth in the direction toward the next pocketin series. and the deeper parts of the pockets being bounded by aconcave curved wall, the channels leading into and out of each pocketbeing substantially narrower than the pockets and being disposed atrelatively opposite sides thereof substantially tangential to saidcurved wall. y

CLARENCE W. BURNHAM.

